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rtoz writes "Ohio State students have come up with a scaled-down version of a power plant combustion system with a unique experimental design--one that chemically converts coal to heat while capturing 99 percent of the carbon dioxide produced in the reaction. Typical coal-fired power plants burn coal to heat water to make steam, which turns the turbines that produce electricity. In chemical looping, the coal isn't burned with fire, but instead chemically combusted in a sealed chamber so that it doesn't pollute the air. This new technology, called coal-direct chemical looping, was pioneered by Liang-Shih Fan, professor of chemical and biomolecular engineering and director of Ohio State's Clean Coal Research Laboratory."

It isn't expensive when all of the senators and representatives from coal burning states insert major tax credits (read: corporate welfare) into bills to pay for such boondoggles. Eventually, such things get passed and we all pay for it.

You should read up on how the federal government subsidies coal liquefaction. It is a complete and total scam.

Because it's not that simple. The free market chooses the cheapest route, but that ignores externalized costs. Externalized costs which are still costs to the rest of us. Right now, that cheapest route is coal, and those externalized costs are very high.

If they raise taxes to implement whatever clean energy you prefer, but prevent climate change, a lot more people will come out ahead on that transaction than lose out. The only reason we're not already doing it is that the few would-be-losers are being astonishingly selfish and short-sighted.

No matter how you slice it you're still left with an assload of carbon that has to go SOMEWHERE so what are you gonna do with it? Frankly that's always been the problem, what to do with all the waste that is left over. TFA I notice is awful light on the details about what EXACTLY if left after this chemical burning, is it a paste, a gel, powder, maybe i missed it but I couldn't find any clear answer on that.

But at the end of the day that is still hundreds of tons of waste you are gonna have to put somewhere, the big question is where because as we saw with Yucca flats pretty much any place you pick is gonna have NIMBYs coming out the woodwork so what are you gonna do with it? This is why I've always supported the new nuclear reactors with reprocessing, it lets you re-use as much as possible until the waste is much smaller and has a much lower half life but no matter how you slice it the stuff left over is gonna have to be put somewhere.

But like coal or hate it we are gonna end up having to use at least some of it because our power needs have gone nowhere but up and this at least sounds like the waste is in solid form instead of gas which will make handling and disposal easier, if not politically then at least physically.

You joke but there is a reason why China is gonna have 25 new nuclear reactors up and running before we get a single one out of committee and that is because no matter what you propose the NIMBYs will try to cock block. Wind? "It'll spoil our view and kill the birds!" Hydro? "It'll run the flow and hurt the fishies!" No matter what tech you use the NIMBYs will come out and try to cock block you here.

So I doubt even being made in Ohio with Ohio coal will help, the NIMBYs will come try and cock block anythi

"Needs of the many outweigh the needs of the few" (ST reference) is the basic theme of China. It's government was forged out of Marxism, so no surprise there. But it cuts both ways. This tenet can dispense misery upon billions of people or lift billions out of poverty in unison. It's also one of the more volatile tenets to rely on vs. one of individuality and self determination. Although the US as of strange reason is locked into a culture struggle of what I like to call "coddle-fication through victimizati

"Needs of the many outweigh the needs of the few" (ST reference) is the basic theme of China.

You are forgetting that most of the western world, having industrialised earlier has been through the "let's trash the environment" stage, and after decades of rivers which burn or stink so badly they make a capital city nearly uninhabitable or spills of toxic waste which cause all sorts of nasty deaths, the western countries have solwly and painfully come to the realisation that it's actually not a very good idea to do all that.

I think this has little to do with cultural values and much to do with industrialisation being difficult and because it is easier to mess things up than not, and therefore comes earlier on in the process.

Also, it's a product of industrialising countries nort really quite realising how much they can mess stuff up until they experience it.

The part that worried me was more the fact that CO2 was still produced, it was just contained within the chamber (the benefit of their technique seemed to just be less/no air space required in the chamber).

Sequestering CO2 is not simple, and is currently done mostly by pumping it into used oil fields. It's not certain whether these costs were factored in.

You are forgetting the other part of the reaction. Air is 78% Nitrogen and 21% Oxygen. In this reaction the Iron removes the Oxygen from the air before it gets into the reactor. So no Nitrogen in the reactor means NOx and no Nitrogen gas to remove from the waste stream.

Sequestering = storage.
That "other problem" you speak of is what gp was referring to. But pedantry aside, tech like this, gasification and other clean coal plans do solve some pieces of the clean energy puzzle and shouldn't be simply cast aside with a flippant "clean coal lol" comment.

Sequestering CO2 is easy. You just don't have a clue how it works. The CO2 is pumped into abandon oil fields at VERY high pressures. This actually results in a return of the field to oil production, as the CO2 forces out more oil. The hydrostatic pressure at that depth is so great that it forces the CO2 into its liquid form. It's not going to suddenly escape to the surfaces, it's miles down and under unfathomable pressure. If we had an earthquake strong enough to crack that, we'd have far more to worry about. Like the really nasty gasses getting released from natural fissures or the earth splitting asunder.

The researchers are about to take their technology to the next level: a larger-scale pilot plant is under construction at the U.S. Department of Energy's National Carbon Capture Center in Wilsonville, AL. Set to begin operations in late 2013, that plant will produce 250 thermal kilowatts using syngas.

Sounds nice, except for the 'combusted in a sealed chamber' bit. How is this going to scale up so they can feed 100 tons/hr through the plant cycle? That is the question.

The key to the technology is the use of tiny metal beads to carry oxygen to the fuel to spur the chemical reaction. For CDCL, the fuel is coal that’s been ground into a powder, and the metal beads are made of iron oxide composites. The coal particles are about 100 micrometers across—about the diameter of a human hair—and the iron beads are larger, about 1.5-2 millimeters across. Chung likened the two different sizes to talcum powder and ice cream sprinkles, though the mix is not nearly so colorful.

The coal and iron oxide are heated to high temperatures, where the materials react with each other. Carbon from the coal binds with the oxygen from the iron oxide and creates carbon dioxide, which rises into a chamber where it is captured.

They ran this for 9 days straight. They only stopped because they were tired. Scaling it up probably is not that much of a problem.The bigger problem might be obtaining both the fuel and the oxidizers in quantity economically.

Coal powered that finely would be rather dangerous, because it has so much surface area. Exposure to air, any spark could set itoff. Handling it would require special care never to let it flow around or accumulate around the crushers. They might have tomake it in a slurry just for safety, then waste more heat drying it before use.

TFA shows them handling bottles of it, and even then they are wearing masks.

Coal is routinely pulverized in order to get it to flow with preheated air through the burners and to provide a large surface area to volume ratio for efficient heating and combustion. 100 micrometers is 0.1 mm, small but not microscopic. This is a typical grain size produced by the pulverizer mills.You really don't want any sort of small powder to get in your lungs. Coal is not particularly dangerous.

Coal contains small amounts of mercury, but not much more so than most other natural ores. The problem with

Coal powered that finely would be rather dangerous, because it has so much surface area. Exposure to air, any spark could set it off.

Uh, yoohoo, over here! [wikipedia.org] They already use coal dust in existing coal burning power plants. I think they have the processing handling issues down for that bit. And, there hasn't been a major coal dust accident since 1962.

BTW, for those that trashed my 'we need to stop burning stuff' [slashdot.org] comments regarding how we generate energy. THIS is exactly what I meant. Applause for the researchers. If this does scale and proves out, they should get a Nobel for it!

This is the kind of science that will save us from Global warming. I know how grand Solar and wind seem grand, but they aren't powering shit yet. Germany is the shining start of renewable energy right now, and they have 20 old school coal fired plants scheduled to be built in the next few decades. We have a LOT of coal. If there's a clean way to use it, we sure as hell better try. It's going to get used one way or another, and 99% efficiency with easy CO2 sequester seems like a pretty smart way to do it.

<quote>This is the kind of science that will save us from Global warming. I know how grand Solar and wind seem grand, but they aren't powering shit yet.</quote>

Wind is powering all sorts of "shit" in Europe. Denmark is pushing about 28% penetration of wind into their power market and many of the surrounding countries have penetrations of 10-20%. And they are building a hell of a lot of offshore wind farms.

Just because the U.S. is slow to get off its ass doesn't mean the rest of the world is.

No other lab has continuously operated a coal-direct chemical looping unit as long as the Ohio State lab did last September. But as doctoral student Elena Chung explained, the experiment could have continued.

“We voluntarily chose to stop the unit. We actually could have run longer, but honestly, it was a mutual decision by Dr. Fan and the students. It was a long and tiring week where we all shared shifts,” she said.

Fan agreed that the nine-day experiment was a success. “In the two years we’ve been running the sub-pilot plants, our CDCL and SCL units have achieved a combined 830 operating hours, which clearly demonstrates the reliability and operability of our design,” he said.

His entire staff of grad students manned the thing and kept feeding it coal for a week and it ran nonstop the whole time, and could have kept going. So this appears to be a solved problem.

As this is chemical, and not combustion, (yes yes, sealed chamber...) it should not take up as nearly as much land as required by current plants. Also, just think of all the job creation all those small power plants will require!!!

Any chemist will tell you that combustion is a chemical reaction. What's interesting about this process is that oxidized iron is used to provide oxygen to "burn" the coal instead of injecting air into the combustion chamber. Not using air lowers the overall gaseous output you need to deal with and the output is a bit cleaner as you don't have to scrub some of the crap like NOX out. You still get sulfur compounds and the heavy metals you'd see with traditional burning.

This is a university press release. They probably talked to him and and asked him questions until he put it that way, because "if we say chemically oxidized no one will know what we're talking about". I bet he doesn't use that word in the paper.

If you really want to be pedantic, your definition is chemically wrong (and the summary actually mentions chemical combustion). Combustion is basically, just an oxydation. Depending how strong/rapid the oxydation is, it is called fire or not.

"Conversion of chemical species" is just another term for "reaction", and "production of heat" through a reaction is the same thing as "exothermic", and a shorter term for "chemical reactions between a fuel and an oxidant" is "oxidation". Thus to put it even shorter: combustion is exothermic oxidation.

Chill mate.My point in reply to PP: "combustion does not require fire"

(as I'm growing old, I don't feel the same geekish urge to be absolutely exact - sometime I don't feel the need of being right)

"New technologies that use fossil fuels should not raise the cost of electricity more than 35 percent, while still capturing more than 90 percent of the resulting carbon dioxide. Based on the current tests with the research-scale plants, Fan and his team believe that they can meet or exceed that requirement"

How does the lack of pollution from the process compare against that generated from the acquisition of the coal?
Is it possible/practical to convert an existing coal power plant?
Is there an appreciable energy/pollution cost to produce the fine powder coal used in the process?
How much energy is consumed or how much pollution is produced in transporting the coal to the reactor?
Is the process itself efficient in regards to the energy output when compared against the total energy costs?

I'm sure there's a lot of other things that don't spring to mind instantly, but I'm certainly not an expert on any of this. Doubts notwithstanding, this is pretty cool.

I'll bite... "How does the lack of pollution from the process compare against that generated from the acquisition of the coal?"In many places, coal is mined using giant shovels that are electrically powered. Underground mines also tend to use electric shovels and other machinery, though not all. From the mine pit or shafts, its either directly loaded into train cars or haul trucks to trains cars. So its pretty much the same.

"Is it possible/practical to convert an existing coal power plant?"Imp

Its not emission-less. If you read his presentation from 2008 you'll see that the C02 is the byproduct of the reaction that is is used to transfer heat to the steam boiler. The C02 still gets generated as before, just now it can be more readily sequestered - assuming that you want to spend the money on that part of the equation.

Even if you don't sequester the carbon and just put it out a smoke stack you're still at an advantage over normal coal burning. One of the major problems with coal burning is not the CO2, but the fly ash that contains heavy metals and causes respiratory problems. This process allows for those heavy metals to be contained in the coal ash which is kept within the plant. Depending on the concentration of metals in the ash it may be economical to mine the ash.

Additionally since the CO2 is pure it can be used industrially without having to distill out the nitrogen that you would if you got it from regular burning.

Spend energy to convert CO2 to another fuel. Great. That has nothing to do with the article unless "unadulterated CO2" is something important. Unfortunately, "unadulterated CO2" is not exciting: it's cheap and hardly more useful than adulterated CO2.

You could use it as feed for algae or other CO2 consuming organisms. Except that currently, the costs for such recapture systems are prohibitive. And in the end, the carbon still ends up in the atmosphere - you just get another fuel cycle out of it.

Maybe they can capture the carbon dioxide, but what are they going to do with it afterwards? Put it in a container and bury it underground? The carbon dioxide will still be there, and the only way to get rid of that is through another reaction, which most likely needs energy to happen.

Another important question is the efficiency. Are they able to produce the same amount of electrical energy from each ton of coal as traditional methods? If their efficiency is worse, then I am very unimpressed. If their efficiency is better, then that may be a more interesting story than that of capturing the carbon dioxide.

The CO2 can be fed to algae tanks to continue another energy production process. It would be easier than doing the same with traditional coal plant if the CO2 is clean and not mixed with ash etc.

And when you burn the oil you got from the algae that formerly fossil CO2 is now in our atmosphere. So maybe you got more energy per ton of CO2 out of it than we normally would. You're still filling the atmosphere with fossil carbon.

well, they could set up a bunch of PV panels to capture sunlight into electricity, and split the CO2 into carbon and oxygen using catalyzed electrolysis. Release the oxygen into the atmosphere, and just dump the carbon into the ground or something.

Or they could scrap the whole coal part of stuff and just use the PV to move those electrons around directly. Adding the PV to the coal system would be less efficient since you are basically using the PV system to reverse the coal system anyway. If the coal system produces X amount of electrical energy releasing Y tonnes of CO2, it is going to take a lot more than X amount of PV electrical energy (I would guess at least 5X being very conservative) in order to turn those Y tonnes of CO2 back into carbon and

Reading between the lines the difference is you aren't getting air into the reactor. So you don't have to heat and separate the Nitrogen. It says the iron pebbles are exposed to air in the reactor but I don't think that is entirely accurate. I think they are exposed after they give up their oxygen to the carbon and are still hot but outside of the actual reactor. This would provide an easy way to chemical way to separate the oxygen from the nitrogen. So the only gaseous byproduct is pure CO2 not CO2 mixed with Nitrogen which is harder to process.

Nor do I understand what the hell is advantageous about it. They admit to oxidiation of the hydrocarbons (ie, burning), heating it to high temperature, and the release of CO2 gas. So exactly what is so great about it?

For a fuel that requires little or no processing it's extremely energy dense. Ultimately the problem wouldn't be with the process but the budget minded power companies. There's a reason "clean coal" is like bigfoot, largely a myth. Clean coal would cost more money reducing profits. It's the reason the industry doesn't remove mercury and coal dust from the exhaust, reduced profits. They even had a government mandate and the still waited until the deadline and are now saying it's too hard. The process can trap 99% of the CO2, the trick is keeping the power companies from not releasing it into the atmosphere to save money. White Diesel is a great source of fuel and second only to natural gas for being a clean fossil fuel but it involves stripping of the CO2 and you are faced with the same problem. Sequestration isn't as simple as it sounds. Compressing huge amounts of CO2 gas takes energy and the underground storage areas don't tend to be near power plants. When you start burning more coal just to store the CO2 from the last batch the efficiency goes way down. If the existing plants had been positioned and built with all this in mind we wouldn't have all these problems. Now there are no cheap and easy solutions. Personally I prefer using algae or greenhouses to store the CO2. Try this approach, pump the CO2 into large cheap greenhouses that grow Kenaf, it's related to hemp but totally legal and interchangeable with industrial hemp. Use as much as industry needs for fiber and seed oil then turn the rest into biochar, a good one to read up on if you aren't familiar. The char can be mixed with farmland improving the soil and it'll absorb the excess fertilizer reducing run off and reducing the amount needed to grow food. The carbon is stored for thousands of years, if not millions. The power companies get to make extra money off the Kenaf and they greatly reduce the CO2 and mercury released. The Mercury will get trapped in the char and the CO2 will be stored as solid carbon. These days they try to solve everything with technology when mother nature has been doing it for billions of years.

They just burn it with pure oxygen instead of with air. The innovation, and it is an innovation IMHO, is that they used iron to capture and transfer the oxygen. This prevents the forming of NOx, which is a good thing. This means they can burn the coal hotter without emitting dangerous amounts of NOx. 1. They let iron pellets rust. Or they buy rust in the first place. 2. They put the rust pellets into the chamber with coal dust. 3. They ignite the mixture (this requires a bit more heat than usual burning. At least 1566 ÂC or 2850.8 F) 4. The coal dust pulls the oxygen out of the rust and binds it with the carbon into quite pure CO2. 5. Heat (a lot of it) 6. Use the heat in a default thermoelectric power plant. 7. The pellets can rust again, to capture oxygen. 8.... 9. Profit.

If they would combine it with an iron smelting plant then the energy required in step 4 to pull the oxygen out of the rust would not be wasted. Then the iron pellets are one of the end results. Of course, then you'd have to emit step 7.

To me this seems familiar. If I am correct this is the way Thermite works, just with aluminium powder instead of coal dust.

Coal isn't clean though. This would clean up the side of the equation where you're burning it. But, it would do absolutely nothing for the mining aspect of it. Which is a huge mess as it stands. If you want to burn things for energy, you're better off starting with something like trees which are mostly carbon neutral as it is.

Sure, it's technically clean if you ignore the incredible damage that it reeks on the landscape, but it's definitely not clean in a practical sense.

Maybe it will. I haven't read the article but there have already been trials where coal is burnt in-situ via using horizontal drilling and air injection. Apparently that works so long as you have full control of all the air getting in.Also, (as I keep telling the fanboys here of 1970's nuclear who don't have the merest clue about developments since), there is not really such a thing as a "clean" industrial process - that's just stupid PR. Al

Clean depends on the definition. There is a waste product associated with every kind of industrial process and every kind of energy production. But the forms of the waste are not all the same nor are they equivalent. Many time people equate the term clean to the quantity of carbon produced during the energy production. If this new technology is viable and it actually contains 99% of the carbon that is a HUGE development. The mining process could be improved and much of the eye sore can be avoided if yo

Hence PR bullshit and a barrier to communication instead of normal language. Just treat such statements as a red flag to indicate that you cannot take the speaker at their word and need a second opinion - the word "clean" is only ever in there to mislead, if it wasn't you'd see "less pollution than X" instead of misleading bullshit.Of course things can be improved but whenever you see "clean" the objective is to improve the perception instead of the reality. One of the place

The problem is that the system has changed since the carbon was taken out of the system. Reintroducing it in such massive quantities over such a short period of time changes things too rapidly for species to adapt to.

Methane emissions are a very serious problem as well, but that has fuck all to do with power generation. You can use methane to produce power, but that's got nothing to do with being carbon neutral.

I've always been confused by "Carbon Neutral" propaganda. For example, we have always had the same amount of carbon in the environment. Just over the years it's been sequestered into oil/coal/etc. However, now if it's been out of commission for thousands of years and it's somehow out of the equation. So burning oil/coal/etc is just normalizing the balance.

No, no, no! You missed the biggest sink for carbon. The one that is orders of magnitude greater than all the others put together: limestone (60 million gigatons vs the 720 gigatons in the atmosphere and the 38,000 gigatons in the oceans). If you think that normalizing the balance with all of the carbon that has been taken out of the environment is a good thing, then you must be from Venus.

There is no burning. Apparently that is the key innovation. The chemical reaction between the coal dust and the rust pellets releases the CO2 in a very controlled manner with the CO2 being separated cleanly rather than mixed up with smoke aka carbon molecules. That must make the CO2 capture much much easier.

Coal is oxidized to produce CO2 and heat. That's "burning", regardless of whether you use air or iron oxides as the oxidizer.

Ummm, sorry, I'm gonna have to go with the Ph.D. in Chemistry [ohio-state.edu] on this one buddy, and he says it's NOT burning. I would not call your comment, Informative. Uninformed, but not informative. Ooo, that's a t-shirt right there...

Because only part of the air gets converted to CO2. Most of the air is nitrogen, and only ~21% is oxygen. Even if you have complete conversion of the oxygen to CO2 (not going to happen), you'd end up with exhaust gas that's mostly nitrogen with some carbon dioxide mixed in. This nitrogen/carbon dioxide mix is difficult to deal with. To do anything with the CO2 you'd have to separate it from the nitrogen and residual oxygen, which gets complicated and expensive.

The hard part is surely the CO2 capture, not the burning.

Exactly. This new method attempts solve that by separating the CO2 generation stage from the air-using stage. If you could effectively separate them, you'll get a pure CO2 stream in one half of the reactor (which if you can keep closed you can pump off into storage tanks) and you'll keep the nitrogen/depleted-oxygen mix in the other half of the reactor, away from your pure CO2.

The way it works is to use iron oxide as an oxygen shuttle. The iron oxide pellets grab oxygen from the air half of the reactor, and are then transferred as a relatively gas-free solid to the coal half of the reactor, where they give up their oxygen to produce a relatively pure stream of CO2. The pellets are then separated from the coal ash and transferred as a relatively gas-free solid back to the air half of the reactor, where they are recharged with oxygen. If you engineer it right, you could conceivably make it a continuous feed operation, where you shuttle the iron oxide beads back and forth through airlocks, keeping most of the CO2 in the sealed reactor where it can be pumped off as a comparatively pure gas.

I think it is because when you burn in air (Mostly Nitrogen) you create NOx compounds. When you burn your exhaust gas contains lots of nitrogen which you have to remove the CO2 from to process. It seems they are using rust as a way to take the oxygen out of the air first so when it reactions with the carbon you get pure CO2 which can easily be compressed without having to deal with Nitrogen and it's oxides.

We already burn a crap load of coal for our electricity. Wouldn't it be great if we worked to make it clean-er ( at least in terms of soot and mercury released into the air)? There isn't much on the horizon that could replace coal over night. We should try to find something will all due haste, but it wouldn't hurt to get the low hanging fruit. Its pretty much what Obama is doing now and its a sensible approach.

We already burn a crap load of coal for our electricity. Wouldn't it be great if we worked to make it clean-er ( at least in terms of soot and mercury released into the air)?

I'm no expert on coal power plants but I'm pretty sure we already do that with scrubbers.

There isn't much on the horizon that could replace coal over night. We should try to find something will all due haste, but it wouldn't hurt to get the low hanging fruit.

Maybe not on the horizon but there is certainly something that has been around for 50+ years that could replace coal overnight. It's called nuclear power.

Its pretty much what Obama is doing now and its a sensible approach.

Is he? I feel like its more about politics than actually solving anything. Instead of pumping money into "green" start-up companies that inevitably spread the wealth among their executives and then disappear in a puff of smoke, the federal government could subsidize th

I'm no expert on coal power plants but I'm pretty sure we already do that with scrubbers.

Scrubbers are typically only required for new plants. Existing plants have very liberal grandfather policies that exempt them. So many companies will simply upgrade existing facilities to keep the grandfather clause. It isn't unlike tearing down a house, save for one wall, then building a new house and then saying it is a 100 year-old house.

Maybe not on the horizon but there is certainly something that has been around for 50+ years that could replace coal overnight. It's called nuclear power.

Traditional nuclear power facilities are expensive. Not to mention that you have to build them in the Styx to appease the NIMBY folks, so you suffer a lot of

Except that the United States has the benefit of cheap methane (CNG). Regionally, you also have cheap hydro in the NW and TV, cheap wind in the upper prairie states and cheap solar in the sun belt.

Coal is only cheap when you exclude the environmental and related health costs. The heavy and radioactive metals expelled as particulate matter are a major source of cancer. The nitrogen oxides expelled are a major contributor to acid rain. People are sorta forgetting those issues in the whole CO2 debate. Las

You realize that a decade ago, europe had access to cheap CNG too. And now it doesn't. And many places in Europe also have restrictions on wood burning as well, and it's now gotten to the point where local governments are no longer enforcing laws on it because the options are 'let people freeze to death' or 'let them illegally cut wood.' Just keep those ideas right going along, never mind that there's a million people in Germany that can't afford electricity because of green energy projects either. Or t

Normal coal burning plants could collect all their exhaust as well. It would cost part of their energy output, but not all

The problem is the other gasses after passing through the combustion chamber, which you may not want to pay for compressing and sequestring. The 78% nitrogen in the atmospheric air will still be there after burning and will contribute to the increased cost.

I wonder if the extra cost of pulverizing the carbon to 0.1mm particle size is a proper offset for the CO2 separation cost from air based combustion.

Also, since the oxygen is delivered bound to iron, the total energy generated but this process will be s

Not only does the system cost a lot of money, it also produces less power per unit of coal.\

There's also the cost of dealing with the captured CO2 as well. If you don't want to spend even more money storing it somewhere you'll have to let it go. There's also more CO2 to get rid of, because it's a less efficient system.

The iron is not a consumable. It is just used to carry oxygen and is re-used.

The problem I see is its much more expensive and reduces the amount of usable energy in the coal. More coal is consumed. You've captured all the CO2 but you still also need to spend more money to deal with it long term.